The minimum firewall ports for a Windows domain controller and linux server

In order for a Linux (client) box to communicate with (and perform NTLM auth) a Windows domain controller through a restrictive firewall you would need the following ports opened at a minimum:

udp 53
tcp/udp 88
tcp/udp 135
tcp 139
tcp 389
tcp 445
tcp/udp 464

Add comments to IPTables firewall rules

Instead of just documenting the IPTables configuration file eg: /etc/sysconfig/iptables with comments (#’s) you can also input comments as part of the ruleset itself. So when you perform iptables -L -v -n you get the following output:

root@server070:[~]: iptables -L -v -n
Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination
  64M 4727M ACCEPT     all  --  *      *             state RELATED,ESTABLISHED
    5   474 ACCEPT     icmp --  *      *  
 202K   27M ACCEPT     all  --  lo     *  
   16   880 ACCEPT     tcp  --  *      *             state NEW tcp dpt:22
 137M   38G ACCEPT     udp  --  *      *             udp dpt:514 /* Syslog traffic */
   28  1664 ACCEPT     tcp  --  *      *             tcp dpt:514 /* Syslog traffic */
41067 2050K ACCEPT     tcp  --  *      *             tcp dpt:9997 /* Universal Forwarder traffic */
    0     0 ACCEPT     tcp  --  *      *             tcp dpt:8089 /* Splunk SSL traffic */
   47  2564 ACCEPT     tcp  --  *      *             tcp dpt:8000 /* Splunk web interface */
14135 1313K LOG        all  --  *      *             limit: avg 5/min burst 5 LOG flags 0 level 7 prefix `iptables denied: '
 218K   21M REJECT     all  --  *      *             reject-with icmp-host-prohibited

All that you need to do use the following example in your configuration file:

root@server070:[~]: cat /etc/sysconfig/iptables
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A INPUT -p udp -m udp --dport 514 -m comment --comment "Syslog traffic" -j ACCEPT
-A INPUT -p tcp -m tcp --dport 514 -m comment --comment "Syslog traffic" -j ACCEPT
-A INPUT -p tcp -m tcp --dport 9997 -m comment --comment "Universal Forwarder traffic" -j ACCEPT
-A INPUT -p tcp -m tcp --dport 8089 -m comment --comment "Splunk SSL traffic" -j ACCEPT
-A INPUT -p tcp -m tcp --dport 8000 -m comment --comment "Splunk web interface" -j ACCEPT
-A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited

Happy commenting!

Configure UTM 220 LCD panel under Linux

I had the task of rebuilding an Astaro UTM 220 with CentOS and the LCD panel looked so lifeless, So I decided to restore it to some version of functional! From my research I can see that the display is LCM-162 and utilises the lcd driver HD44780.

In a nut shell here is what I did:

  • Download LCDproc (
  • Modify: lcdproc-0.5.6/server/drivers/hd44780-ext8bit.c


#define RS  STRB
#define RW  LF
#define EN1 INIT 


#define RS  SEL
#define RW  INIT
#define EN1 LF 
  • compile it with option: ‘./configure –enable-drivers=hd44780′
  • make && make install
  • Modify: /usr/local/etc/LCDd.conf


  • Line 53: Driver=hd44780
  • Line 502: ConnectionType=8bit
  • Line 509: Device=/dev/parport0
  • Line 544: Size=16×2

Test it:

LCDd -f -r 4 -c /usr/local/etc/LCDd.conf &
lcdproc -f -s localhost -p 13666 C M L

If it works its just a matter of copying: scripts/init-LCDd.rpm and scripts/init-lcdproc.rpm to /etc/init.d and configuring chkconfig properly.

Hopefully that helps.